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<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>

<body>
    <script>
        // var o = {

        //     age: 18,

        //     a: {

        //         fn: function () {

        //             console.log(this.age);

        //         }

        //     }
        // }
        // o.a.fn();
        var person = {

            sex: "女",

            fn: function () {

                console.log(this.sex);

            }

        }

        person.fn()
    </script>
</body>

</html>